Gastone Gilli and Paola Gilli
- Published in print:
- 2009
- Published Online:
- September 2009
- ISBN:
- 9780199558964
- eISBN:
- 9780191720949
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199558964.003.0004
- Subject:
- Physics, Crystallography: Physics
Crystallographic databases collect some 300,000 structures, tens of thousands including one or more H-bonds. This impressive archive take in all varieties of inter- and intra-molecular H-bonds of any ...
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Crystallographic databases collect some 300,000 structures, tens of thousands including one or more H-bonds. This impressive archive take in all varieties of inter- and intra-molecular H-bonds of any strength made by all possible atoms and can be asked any question on the H-bond nature provided we know how to do it. This chapter selects appropriate methods (crystal-structure correlations, Pauling's bond number, bond-number conservation, and Lippincott and Schroeder's method) and applies them to large sets of structural data representative of the most important H-bond classes. Particular attention is paid to strong O-H···O, N-H···N, and N-H···O/O-H···N resonance-assisted H-bonds (RAHBs) and their interpretation by different theoretical models. Three other classes of strong charge-assisted H-bonds (CAHBs) are identified and the H-bond classification is completed in six classes (the chemical leitmotifs). Results are interpreted in terms of electrostatic-covalent H-bond model (ECHBM) and PA/pKa equalization principle. A general equation linking H-bond energies and geometries is attempted.Less
Crystallographic databases collect some 300,000 structures, tens of thousands including one or more H-bonds. This impressive archive take in all varieties of inter- and intra-molecular H-bonds of any strength made by all possible atoms and can be asked any question on the H-bond nature provided we know how to do it. This chapter selects appropriate methods (crystal-structure correlations, Pauling's bond number, bond-number conservation, and Lippincott and Schroeder's method) and applies them to large sets of structural data representative of the most important H-bond classes. Particular attention is paid to strong O-H···O, N-H···N, and N-H···O/O-H···N resonance-assisted H-bonds (RAHBs) and their interpretation by different theoretical models. Three other classes of strong charge-assisted H-bonds (CAHBs) are identified and the H-bond classification is completed in six classes (the chemical leitmotifs). Results are interpreted in terms of electrostatic-covalent H-bond model (ECHBM) and PA/pKa equalization principle. A general equation linking H-bond energies and geometries is attempted.
